EP3551323A1

EP3551323A1 - Mixing blade comprising wear element and method for attaching a wear element to a base part of a mixing blade

Info

Publication number: EP3551323A1
Application number: EP17822573.6A
Authority: EP
Inventors: Clemens Schmitt; Simon Blau
Original assignee: Maschinenfabrik Gustav Eirich GmbH and Co KG
Current assignee: Maschinenfabrik Gustav Eirich GmbH and Co KG
Priority date: 2016-12-07
Filing date: 2017-12-05
Publication date: 2019-10-16
Also published as: CN110049812B; DE102016123712A1; WO2018104286A1; CN110049812A

Abstract

The present invention relates to a mixing blade consisting of a base part (1) which can be attached to a shaft, and a wear element (8), wherein the wear element (8) is or can be releasably attached to the base part (1). To provide a mixing blade that allows the wear element (8) to be easily released from the base part (1), the invention proposes that to attach the wear element (8) to the base part (1), at least one element from the group consisting of the wear element (8), the base part (1) and an intermediate element arranged optionally at least partially between the wear element (8) and the base part (1) is elastically deformed such that it exerts a force on another element from the group.

Description

Blade with wear element and method for attaching a

Wear element on a base of a mixing blade

The present invention relates to a mixing blade consisting of a fastened to a shaft base and a wear element, wherein the wear element is releasably attached or attachable to the base. Furthermore, the present invention relates to a method for mounting a wear element on the base.

Such a mixing blade with detachable wear element is known, for example, from DE 10 2005 019 010 A1. Such mixing blades are intended for use in mixers in which granular, abrasive materials are processed.

Mixers are known which have one or more mixer shafts arranged perpendicularly to the mixing container bottom and which are provided with mixing blades arranged in several planes and extending radially. The mixing vanes are generally of substantially rectangular cross-section, this cross-sectional shape sometimes being tapered towards the front edge of the mixing blade, so that the mixing vanes have the overall shape of a flat, one-sided rectangular trapezium. The leading edge of the mixing blades is the front edge in the direction of rotation of the corresponding rotor, which comes into engagement with the material to be mixed with the rotor rotating in front of the remaining parts of the mixing blade. The base generally consists of one piece and is made of a relatively soft material. To protect against wear, it is known to apply wear elements on the base. These can be soldered on, however, whereby the mixing blades are only interchangeable as a whole. In the cited DE 10 2005 019 010 A1, therefore, mixing blades having a detachable wearing element have already been described, but here the wearing elements have been screwed to the base part.

Although this variant offers the possibility to replace only the wear element, in practice, however, the dismantling of the wear element from the base often difficult, since the mounting screws are also damaged and dirty, so that a loosening of the screws is not always readily possible. Against the background of the described prior art, it is therefore an object of the present invention to provide a mixing blade which allows easy release of the wear element from the base. According to the invention this is achieved in that for fixing the wear element on the base at least one element from the group consisting of the wear element, the base and an optionally at least partially disposed between the wear element and base intermediate element is elastically deformed so that it is a force on another Element from the group exercises.

By this measure can be dispensed with any further measure for attachment of the wear element on the base.

In one embodiment, it would be possible, for example, for the wear element to be designed in the form of a sleeve so that it has a passage recess into which the base part can engage. Here, the outer contour of the base is slightly larger than the inner contour of the wear element, so cooled for mounting the base and / or the wear element must be heated, whereby the inner contour of the recess of the wear element widens and the wear element can be pushed over the base. As soon as the temperatures of the base part and the wear element have become equal again, the wear element sits firmly on the base part, resulting in an elastic deformation of both the wear element and the base part.

If the wear element to be released again from the base, the wear element must be reheated and the base as possible cooled.

The elastic deformation of at least one element thus leads to a distortion of the wear element on the base part. It is not excluded that in addition to the elastic deformation takes place a plastic deformation.

Under a sleeve-shaped wear element is also understood a wear element whose recess does not completely surround the base, but only partially. Therefore, "slotted" sleeves are also conceivable in the longitudinal direction, whereby the slot should extend in the circumferential direction by less than 180 °. Sleeve-shaped thus means any shape which is able to enclose the base part over a circumferential angle of more than 180 °.

In a preferred embodiment, an intermediate element is arranged between the wear element and the base part, wherein the intermediate element has a greater elasticity than the base part and wear element. In the attachment of the wear element on the base part, the intermediate element is then substantially elastically deformed, so that it is supported both on the base part and on the wear element. The intermediate element may consist of a plastic, preferably of an elastomer and particularly preferably of a fluororubber. For example, it would be possible for the base part to have circular grooves in which elastic O-rings are arranged so that the O-ring between the wear element on the one hand and the base part on the other hand is elastically deformed in the fastened state and thus makes it possible to fix the wear element to the base part. light.

In particular, if an intermediate element is provided, an additional plastic deformation of the intermediate element may be desired. The force exerted by the elastic deformation on another element should be greater than the force normally applied to the wear element during operation of the mixing blades. In general, the mixing vanes are fixed to a mixing shaft and the mixing shaft rotates about its axis, so that a centrifugal force is exerted on the mixing vanes, the force exerted by the elastic deformation should therefore be greater than the centrifugal force.

In a further preferred embodiment, the base has an elongate shape with a longitudinal direction. In the same way, also the intermediate element has an elongated shape with a longitudinal direction and the longitudinal direction of the intermediate element is arranged parallel or coaxial with the longitudinal direction of the base part. Thus, for example, the intermediate element may be an elongated rubber seal, which is elastically deformed between the base part and the wear element.

In a further preferred embodiment, the mixing blade on a plurality of wear elements, which are fastened or fixed in the longitudinal direction of the base in succession to the base. This embodiment makes it possible for the wear elements to be used for mixing blades of different lengths, with mixing blades of greater length simply attaching more wear elements one after the other to the mixing blade. It is particularly preferred if at least one wear element has a passage recess and a wear element has a pocket recess. To mount the wear elements on the base part, the wear elements are first pushed onto the base part with a passage recess, so that the base part extends through the passage recess. Finally, the wear element is pushed with Sackausnehmung on the base so that it covers the base completely like a kind of hood.

In a further preferred embodiment, when the wear elements are attached to the base, the intermediate element contacts at least two wear elements. Particularly preferably, the intermediate element comes into contact with all the wear elements.

In a further preferred embodiment, sealing elements are arranged between the wear elements, wherein the sealing elements are preferably made of plastic and best of all made of an elastomer. Alternatively, the sealing elements could also be made of silicone.

This measure prevents in operation that dust or small components of the mixed material passes between adjacent wear elements and passes to the base or even between adjacent wear elements sets and pushes them apart. In addition, it is not necessary to manufacture the mutually facing end faces of adjacent wear elements with small tolerances, since any deviations are compensated by the sealing elements. In one embodiment, without sealing elements, however, the end surfaces should be made with high precision, so that as little dust as possible can pass to the base in operation between adjacent wear elements. In a further preferred embodiment, the intermediate element is arranged between the base part and the wear element such that the base part and the wear element do not touch each other.

This has the advantage that base and wear element can be made of materials with significantly different coefficients of thermal expansion without problems in the operational heating of the mixing blade problems due to the different extent of the two elements, since then only the intermediate element more or less expands.

In a further preferred embodiment, the wear element has a recess with an inner contour for receiving a base part, the base part has an outer contour, wherein the inner contour of the recess of the wear element and the outer contour of the base are formed corresponding to each other so that when in the recess of the wear element Mentes inserted base part between the base and wear element at least partially remains a distance which is dimensioned such that an elastically deformed intermediate element can be accommodated. With regard to the base part, the object mentioned at the outset is achieved by a base part having a fastening section which is intended to be connected to a shaft and a working section, wherein the working section is arranged on the fastening section, the base part having a jacket surface and a fastening section having opposite end face. In this case, the lateral surface has at least one recess for receiving an intermediate element, wherein preferably the recess is designed as a groove extending from the fastening section via the working section to the end face, the groove preferably having a part-circular cross-section. The base may have a substantially quadrangular cross-section, the groove preferably extending along an edge of the base. In this case, the cross section may be exactly quadrangular, but embodiments are also conceivable in which the corners are rounded or individual sides are concave or convex curved.

With regard to the wear element, the object mentioned is achieved by a wear element with a recess for receiving a base part, which forms an inner contour of the wear element. In this case, the inner contour has at least one recess for receiving an intermediate element, wherein preferably the recess is a groove which extends along the recess, wherein best of all the groove has a part-circular cross-section. The use of the wear element according to the invention does not exclude that the base also has a corresponding recess. The intermediate element is then arranged such that it lies both in the recess of the base element and in the recess of the wear element.

In a preferred embodiment, the recess extends along a straight line and best along the entire length of the recess.

In a particularly preferred embodiment, the recess extends along the entire wear element. In this case, the recess can extend through the wear element, so that the wear element completely surrounds the base part when the base part is arranged in the recess.

The present invention also relates to a mixer with a mixing container and a mixer shaft to which at least one mixing blade of the type described is attached. In a preferred embodiment, the mixing vessel rotates about a fixed mixer shaft. Alternatively, you can turn the mixer shaft. In addition, it is also possible that both mixer shaft and mixing container rotate, in which case the mixer shaft is preferably arranged eccentrically in the mixing vessel, ie, the mixing vessel rotation axis and the mixer shaft axis are arranged spaced from each other.

With regard to the method, the object mentioned at the outset is achieved by a method for fastening a wearing element to a base part of a mixing wing, having the following steps:

a) provision of a base part with a receiving surface for receiving a wear element,

b) providing a wear element with a recess for receiving the base part, wherein the recess is dimensioned such that the base part can be pushed into the recess, wherein between the receiving surface and recess at least partially a gap with a gap width b remains,

c) providing an intermediate member having a thickness d, where d is greater than b; d) tensioning the intermediate member in a direction such that the thickness of the intermediate member decreases such that the thickness ds _P ann is less than b, e ) Positioning of base, intermediate element and wear element such that the base is positioned in the recess and the intermediate element is at least partially disposed in the gap, and

f) releasing the tension, so that the thickness of the intermediate element increases again, and the intermediate element exerts a force on the base and wear element.

In this case, the base parts according to the invention, wear elements, intermediate elements and mixing blades can be used.

The gap width does not have to be constant. For example, the gap could also be wedge-shaped. Further advantages, features and possible applications of the present invention will become apparent from the following description of preferred embodiments and the associated figures. Show it:

FIG. 1 shows a perspective view of a basic part of a first embodiment,

FIG. 2 shows a perspective view of a second embodiment of the base part with a pushed-on wear element, Figure 3 is a perspective view of the base of Figure 2, which is completely with

Wear elements is equipped,

FIG. 4 shows a perspective view similar to FIG. 3, with the end piece being shown in a partially sectioned illustration,

FIG. 5 shows a cross-sectional view through the embodiments of FIGS. 2 to 4,

FIG. 6 shows a sectional view through a third embodiment of the invention,

7 shows a sectional view through a fourth embodiment of the invention,

FIG. 8 shows a sectional view through a fifth embodiment of the invention,

9 shows a sectional view through a sixth embodiment of the invention, FIG. 10 shows a perspective view of a basic part of a seventh embodiment of the invention,

Figure 1 1 is a sectional view through a mixing blade of an eighth embodiment of the invention and

Figure 12 is a sectional view through a mixing blade of a ninth embodiment of the invention.

FIG. 1 shows a perspective view of a base part 1 of a first embodiment of the invention. The base 1 has a mounting portion 2 with a bore 3. The base can be fastened with its attachment portion 2 to a mixer shaft. Furthermore, the base part 1 has a working section 4, which is delimited by an end face 5 facing away from the fastening section 2. The working portion 4 has a substantially rectangular cross-section, wherein in the corners recesses 6 have been attached, which extend substantially over the entire length of the working portion 4 to the attachment portion 2.

FIG. 2 shows a second embodiment of a base part 1. This embodiment differs from the embodiment shown in Figure 1 only by a threaded bore 16 and two holes 17 for receiving anti-rotation pins 12. In the groove-like recesses 6 plastic cords 7 of fluorine rubber (FPM) are now inserted. If these plastic cords stretched in the longitudinal direction, so they reduce their cross-section. In the tensioned state, therefore, a wearing element 8 can be pushed with a passage opening over the base part 1 or its working section 4. As soon as the wear element 8 is in its desired position, the tension of the plastic cord 7 can be reduced so that the cross section expands again and the base part 1 and wear element 8 are braced against each other. In Figure 3, the state is shown in which two wear elements 8 have been pushed with through hole on the base 1. Finally, in this embodiment, a closure element 9 is screwed to the base 1. For clarity, a partially sectioned view is shown in FIG. It can be seen that the closing element 9 by means of a screw 1 1, which is arranged in a stepped bore, is bolted to the base member 1. The stepped bore is closed by means of a cover 10. To prevent twisting of the closing element 9, pins 12 are provided which are positioned in corresponding bore in both the closing element 9 and the base element 1.

FIG. 5 shows a sectional view through the embodiment of FIGS. 2 to 4.

The cross-sectional area of the wear element 8 is substantially trapezoidal, but opposite corners are significantly rounded. In principle, the outer contour can be freely selected and is trapezoidal here by way of example. It can be seen that the recesses 6 remain in the assembled state, but whose cross section is smaller than the cross section of the plastic cord in the relaxed state. By the four plastic cords, which are arranged in the corresponding recesses 6, the wear element 8 is held relative to the base 1 in its position, so that a gap between the base 1 and the wear element 8 forms and the two parts do not touch each other.

FIG. 6 shows a sectional view of a third embodiment of the invention. As in the first embodiment, a wear element 9 has been pushed over the base 1 here as well. Instead of the end element 9, however, a further wear element 13 is arranged here. This wearing element 13 is pushed over the frontal region of the base part 1 in such a way that it projects beyond the edge of the base part facing away from the fastening section. Thereby, a frontal recess 18 is formed in the mixing blade, which can either remain empty so that it can be filled with mix, or with another material, such as e.g. Building foam, can be completed.

Between the two wear elements 8 and 13, a sealing element 14 is provided to prevent that accumulates powdery material between the sleeves and these apart with time. In addition, the requirements for the flatness of the end faces of the wear elements can be reduced by this measure.

FIG. 7 shows a fourth embodiment of the invention. You can only see a cross section. The wear element 8 'is shown here with a different cross-sectional shape. It has a substantially rectangular recess with rounded corners. In the base 1, longitudinally extending recesses 6 are introduced, are inserted in the plastic cords 7. FIG. 8 shows a fifth embodiment of the invention. This embodiment essentially differs from the embodiment in Figure 7 in that the recesses 6 are mounted not only in the base part 1, but also in the wear element 8 "Alternatively, the recesses 6 could also be arranged only in the wear element 6 shows the sixth embodiment of the invention, from which it can be seen that the wearing element 8 "'does not necessarily have to completely enclose the base part 1. The remaining slot can either remain open or be foamed, for example. The slot is provided at a position at which no wear is expected during operation, so that no wear element must be present here.

In addition, the recesses 6 need not necessarily be arranged on the edges of the base part 1, but can, as shown in Figure 9, in principle be positioned at any point. Furthermore, a seventh embodiment of the invention is shown in FIG. The base V here has a plurality of annular grooves, in which corresponding elastic O-rings can be used. The wear elements can then be pushed over the base V, so that the O-rings are compressed in the grooves 15. Figure 1 1 shows a sectional view through a mixing blade according to an eighth embodiment of the invention. In comparison with the fifth embodiment of the invention shown in FIG. 8, the base part does not have a rectangular cross section but a trapezoidal cross section. The cross section of the base part is adapted to the outer contour of the closure element 8 ^"" such that the thickness of the wear element is uniform (di = d2). This is particularly advantageous if the wear element is made as a sintered part, since the risk of cracks is minimized.

Finally, FIG. 12 shows a sectional view through a mixing blade according to a ninth embodiment of the invention. Compared to the fifth embodiment of the invention shown in FIG. 8, the base part 1 "" has guide ribs 19 on both sides, which engage in corresponding guide grooves 20 in the wear element 8 ""'and mount the wear element 8 ""' on the base part V ". facilitate. reference numeral

base

attachment section

drilling

working section

face

recess

Plastic cord

, 8'-8 "" 'wear element

terminating element

0 cover

1 screw

2 pen

3 wear element

4 sealing element

5 groove

6 tapped hole

7 Hole for anti-rotation 8 recess

9 leadership advantage

0 guide groove

Claims

P a n t a n s p r e c h e

Mixing vanes consisting of a fastened to a shaft base and a wear element, wherein the wear element is releasably attached or attachable to the base, characterized in that for fixing the wear element on the base at least one element from the group consisting of the wear element, the base and a optionally at least partially between the wear element and the base part arranged intermediate element is elastically deformed so that it exerts a force on another element from the group.

A mixing blade according to claim 1, characterized in that the base part according to one of claims 1 1 or 12 and / or the wear element is designed according to one of claims 13 to 15.

Blade according to claim 1 or 2, characterized in that between the wear element and the base part, an intermediate element is arranged, wherein the intermediate element has a greater elasticity than the base part and wear element.

A mixing blade according to claim 3, characterized in that the intermediate element consists of a plastic, preferably of an elastomer and particularly preferably of a fluororubber.

A mixing blade according to claim 3 or 4, characterized in that the base part has an elongate shape with a longitudinal direction, that the intermediate element has an elongated shape with a longitudinal direction and that the longitudinal direction of the intermediate element is arranged parallel or coaxial with the longitudinal direction of the base part, preferably Intermediate element is a plastic cord.

A mixing blade according to any one of claims 2 to 5, characterized in that the mixing blade has a plurality of wear elements, which are fastened or secured in the longitudinal direction of the base one behind the other on the base, preferably at least one wear element in a longitudinal direction of the base projecting beyond this.

Blend according to claim 6, characterized in that the intermediate element, when the wear elements are fixed to the base, is in contact with at least two wear elements. A mixing blade according to claim 6 or 7, characterized in that between the wear elements sealing elements are arranged, wherein the sealing elements are preferably made of plastic and best of an elastomer.

Blade according to one of claims 3 to 8, characterized in that the intermediate element are arranged between the base part and the wear element such that the base part and the wear element do not touch.

0. mixing blade according to one of claims 3 to 9, characterized in that the wear element has a recess with an inner contour for receiving a base part, that the base part has an outer contour, wherein the inner contour of the recess of the wear element and the outer contour of the base in such a way correspond to each other are formed, that at least inserted in the recess of the wear element base between the base and wear element, a distance remains, which is dimensioned such that an elastically deformed intermediate element can be accommodated.

A base member attachable to a shaft of a mixer, the base member having a fixing portion adapted to be connected to a shaft and a working portion, the working portion being disposed on the fixing portion, and a shell surface and a shell Fastening portion facing away from end face, characterized in that the lateral surface has at least one recess for receiving an intermediate element, wherein preferably the recess is formed as a extending from the mounting portion on the working portion to the end face groove, wherein the groove is best a part-circular cross-section ,

2. Base according to claim 1 1, characterized in that the base part has a substantially quadrangular cross-section, wherein the groove preferably extends along an edge of the base part.

3. wear element for attachment to a base, which is fastened to a shaft, wherein the wear element has a recess for receiving a base, which forms an inner contour of the wear element, characterized in that the inner contour has at least one recess, wherein preferably the recess a Groove which extends along the recess, wherein best of the groove has a part-circular cross-section. Wear element according to claim 13, characterized in that the recess is a through-hole.

Wear element according to claim 13, characterized in that the recess is a blind recess.

Mixer with a mixing container and a mixer shaft on the at least one mixing blade according to one of claims 1 to 10 is arranged.

Method of attaching a wear element to a base of a mixing blade, comprising the steps of:

a) providing a base part with a receiving surface for receiving a wear element,

b) providing a wear element with a recess for receiving the base part, wherein the recess is dimensioned such that the base part can be pushed into the recess, wherein at least partially a gap with a gap width b remains between the receiving surface and recess, c) providing an intermediate element d) with a thickness d, where d is greater than b, d) under tensile stress of the intermediate element in a direction such that the thickness of the intermediate element is reduced such that the thickness ds _P ann is smaller than b,

e) positioning of the base part, intermediate element and wear element such that the base is positioned in the recess and the intermediate element is at least partially disposed in the gap, and

18. The method according to claim 17, characterized in that in step a) a base according to one of claims 1 1 to 12 and / or in step b) a wear element according to one of claims 13 to 15 is provided.